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Hello everyone!
Briefly introduction, I would like to communicate and test the following hardwares:
1- Omron CP1E (using an Option Port CP1W-CIF11) ; and
2- Arduino Nano using MAX485 RS485 transceiver.
The CP1E will operate in "Modbus-RTU simple master" as illustrated in image 01. The arduino will be in slave mode address 1 and the library used is "SimpleModbus NG" ( https://github.com/angeloc/simplemodbusng/tree/master/SimpleModbusSlave ).
Taking the sample in official manual ( https://industrial.omron.eu/en/services-support/technical-tools/downloads#cp1e ) , pages 248-253 in the "CP1E CPU Unit Software User's Manual" (Image 04) describes a sample communication to an "Inverter Slave".
I want to use the Arduino Slave as the Inverter Slave just to be sure that all previous steps are correct.
Therefore, I would like to know:
1- As illustrated in Image 02, Am I missing any resistors?
2- Should I connect the GND to the FG?
3- In this scenario, the DIP switch setup should be as illustrated in image 03? Only DIP4 is OFF.
4- Can I test it just forcing A641.00 and checking the DM Area Data, as shown in Image 05?
The code used in it is the following:
// Wiring: Arduino and MAX485
// RX0 - RO
// TX1 - DI
// D2 - DE/RE
#include "SimpleModbusSlave.h"
enum {
REGISTER_0,
REGISTER_1,
REGISTER_2,
REGISTER_3,
REGISTER_4,
REGISTER_5,
REGISTER_6,
REGISTER_7,
REGISTER_8,
TOTAL_REGS_SIZE
};
unsigned int holdingRegs[TOTAL_REGS_SIZE] = { 0, 1, 2, 3, 4, 5, 6, 7, 8 };
void setup() {
modbus_configure(&Serial, 9600, SERIAL_8N1, 1, 2, TOTAL_REGS_SIZE, holdingRegs);
}
void loop() {
modbus_update();
}
Any answer can be helpful. Thank you for your time!
Regards,
Jose.